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At least 523 records · Page 29Linked to original sources
PubMed1994

A comprehensive study of physical parameters, biomechanical properties, and statistical correlations of iliac crest bone wedges used in spinal fusion surgery. I. Physical parameters and their correlations.

Iliac crest bone wedges are commonly used in spinal fusion procedures and must be capable of withstanding considerable mechanical stress during the healing process. The variability of "quality" of bone materials used in the production of bone wedges suggests that some bone materials may not be suitable for use in vertebral fusion procedures and some quantifiable means of predicting the suitability of bone wedges would be desirable. A total of 250 iliac crest wedges were used in this study. Physical parameters of iliac crest wedges, such as total cross-sectional area, cancellous cross-sectional area, cortical cross-sectional area, percentage of cortical cross-sectional area, "width," and apparent density were determined. The statistical correlations among physical parameters were investigated. These correlations revealed that the relative percentage of cortical and cancellous bone remained fairly constant at 41% and 59%, respectively, regardless of total cross-sectional area of a wedge, that apparent density did not appreciably change with donor age, and that ash (inorganic) and organic content (weight) correlated well with the apparent density.

Aging↗
PubMed1994

Physical mapping of 38 highly informative genetic markers to 10 intervals of chromosome 11q: integration of the physical and genetic maps.

A large number of highly polymorphic microsatellite markers particularly suitable for genetic linkage analysis have recently been developed. In order to facilitate integration of the genetic maps of chromosome 11q generated using these types of markers with the physical maps of 11q currently being assembled, we have regionally assigned the Genethon markers and the 11q designated index plus other commonly used polymorphic markers to ten physical intervals of 11q. These intervals are defined by translocation breakpoints immortalized in somatic cell hybrid lines and can therefore serve as readily accessible and stable landmarks for detailed map integration and facilitate the derivation and placement of new markers and cloned contigs.

Chromosome Mapping↗
PubMed1990

Physical illness and depression: the effects of acute physical illness on the mental state of psychiatric inpatients.

A patient is described with a severe agitated depression who made a dramatic recovery following an acute myocardial infarction. A retrospective case notes study was conducted to investigate the effects of a sudden physical illness on the mental state of a group of psychiatric inpatients. Seven patients were identified with agitated depression who improved considerably following an acute life-threatening physical event. Patients with other forms of depression, schizophrenia and schizoaffective disorder showed either no change or underwent a deterioration in mental state.

Acute Disease↗
PubMed2001

The physical functioning inventory: a procedure for assessing physical function in adults.

The Physical Functioning Inventory, an instrument designed to assess changes in how and how often activities are performed in persons reporting difficulty with a task as well as in those who do not, is described. The measure is designed for adults. Interrater and test-retest reliability were assessed with active participants in the Baltimore Longitudinal Study of Aging (BLSA). Percentage agreement ranged from 63% to 100%. The instrument was also given to 392 inactive BLSA participants as part of a follow-up telephone interview. Fifty-eight percent of the respondents reported no difficulty in performing a task, yet reported a change in how often they performed that task. The results indicate that the instrument is reliable and effective in detecting early stages of disability in activities of daily living, instrumental activities of daily living, and mobility. The instrument is somewhat less reliable for moderate and strenuous physical activities.

Activities of Daily Living↗
PubMed2005

The Physical Activity Resource Assessment (PARA) instrument: evaluating features, amenities and incivilities of physical activity resources in urban neighborhoods.

BACKGROUND: Neighborhood environment factors may influence physical activity (PA). The purpose of this study was to develop and test a brief instrument to systematically document and describe the type, features, amenities, quality and incivilities of a variety of PA resources. METHOD: The one-page Physical Activity Resource Assessment (PARA) instrument was developed to assess all publicly available PA resources in thirteen urban lower income, high ethnic minority concentration neighborhoods that surrounded public housing developments (HDs) and four higher income, low ethnic minority concentration comparison neighborhoods. Neighborhoods had similar population density and connectivity. Trained field coders rated 97 PA resources (including parks, churches, schools, sports facilities, fitness centers, community centers, and trails) on location, type, cost, features, amenities, quality and incivilities. Assessments typically took about 10 minutes to complete. RESULTS: HD neighborhoods had a mean of 4.9 PA resources (n = 73) with considerable variability in the type of resources available for each neighborhood. Comparison neighborhoods had a mean of 6 resources (n = 24). Most resources were accessible at no cost (82%). Resources in both types of neighborhoods typically had about 2 to 3 PA features and amenities, and the quality was usually mediocre to good in both types of neighborhoods. Incivilities at PA resources in HD neighborhoods were significantly more common than in comparison neighborhoods. CONCLUSION: Although PA resources were similar in number, features and amenities, the overall appearance of the resources in HD neighborhoods was much worse as indicated by substantially worse incivilities ratings in HD neighborhoods. The more comprehensive assessment, including features, amenities and incivilities, provided by the PARA may be important to distinguish between PA resources in lower and higher deprivation areas.

Journal Article↗
PubMed2005

Modifying physical activity in a multiethnic sample of low-income women: one-year results from the IMPACT (Increasing Motivation for Physical ACTivity) project.

BACKGROUND: Ethnic minorities or those with low socioeconomic status (SES) are at increased risk of cardiovascular disease, type 2 diabetes, and all-cause mortality, compared to higher SES Whites. National surveys also indicate that low-income, ethnic minority women have the highest rates of inactivity in the United States. PURPOSE: This study (the Increasing Motivation for Physical ACTivity or IMPACT study) promoted adoption and maintenance of physical activity (PA) in sedentary, low-income women participating in federally funded job training programs. METHODS: The study consisted of 2 months of weekly 1-hr classes, then random assignment to 10 months of either home-based telephone counseling for PA plus information and feedback via mailed newsletters (Phone + Mail Counseling condition) or just the mailed newsletters (Mail Support condition). The IMPACT intervention included behavior change strategies for PA as well as discussions related to motivational readiness for PA change. Participants completed surveys and physiological assessments at baseline after the classes ended (i.e., at 10 weeks) and at 6 and 12 months postbaseline. Seventy-three percent of randomized participants (n = 72) were Latina, with a mean age of 32 +/- 10 years. More than half the women had not completed high school, and 73% had an annual income less than 20,000 dollars. RESULTS: After 10 months of a home-based intervention, women in the phone + mail counseling condition had significantly greater increases in estimated total energy expenditure compared to women in the mail support condition (p < .05). CONCLUSIONS: Regular PA counseling delivered via the telephone and through the mail appears effective for encouraging regular PA among low-income women transitioning from welfare or job training to the workforce.

Adolescent↗
PubMed1993

Compendium of physical activities: classification of energy costs of human physical activities.

A coding scheme is presented for classifying physical activity by rate of energy expenditure, i.e., by intensity. Energy cost was established by a review of published and unpublished data. This coding scheme employs five digits that classify activity by purpose (i.e., sports, occupation, self-care), the specific type of activity, and its intensity as the ratio of work metabolic rate to resting metabolic rate (METs). Energy expenditure in kilocalories or kilocalories per kilogram body weight can be estimated for all activities, specific activities, or activity types. General use of this coding system would enhance the comparability of results across studies using self reports of physical activity.

Energy Metabolism↗
PubMed2004

Associations of perceived social and physical environmental supports with physical activity and walking behavior.

We evaluated perceived social and environmental supports for physical activity and walking using multivariable modeling. Perceptions were obtained on a sample of households in a southeastern county. Respondents were classified according to physical activity levels and walking behaviors. Respondents who had good street lighting; trusted their neighbors; and used private recreational facilities, parks, playgrounds, and sports fields were more likely to be regularly active. Perceiving neighbors as being active, having access to sidewalks, and using malls were associated with regular walking.

Adult↗
PubMed1999

[A study of mental and physical reactions after the Hanshin-Awaji Earthquake: mental and physical conditions of female undergraduate students immediately after, 2 months after, and 9 months after the earthquake].

This study assessed how time brings out changes in one's mental and physical reactions to traumatic experiences. Two surveys were conducted on students of Kobe College, located at one of the areas hardest hit by the Hanshin-Awaji Earthquake in January, 1995. Much of the traumatic reactions decreased in strength through January to March, while feelings of survival guilt did not. Guilt feelings of those whose housing were destroyed increased in March, and kept its level even in October. Although general health conditions of those surveyed in October was normal, several post-traumatic reactions increased in October as compared with March. The rate of recovery from post-traumatic reactions seemed to very according to the depth of one's psychological suffering, to one's financial situation, and to the presence of social support. The factor analysis on the items of mental and physical reactions yielded seven factors. The factor of highest eigenvalue in January was one named "anxiety about after-quake tremors", however, this was replaced by one named "emotional confusions" in March.

Data Collection↗
PubMed2000

[Asymmetry of signs of finger dermatoglyphics, physical potential and physical qualities of a man].

Correlation between asymmetry of total signs of digital dermatoglyphs and general level of physical potential and basic physical qualities was studied. Highly qualified sportsmen were examined: men (231) and women (95) 20-38 yrs old; MPU students--men (106) and women (92) 17-20 yrs old; children with infantile cerebral paralysis, boys (12) and girls (42) 4-13 yrs old and parents of these children, man (12) and women (42) 25-48 yrs old. Variability of asymmetry of basic of digital dermatoglyfied was associated with sexual peculiarities of dominance of right or left hemisphere in functional asymmetry of brain.

Adolescent↗
PubMed1976

Physical attractiveness, physical effectiveness, and self-concept in late adolescents.

The differential role of various body attitudes in predicting the self-concepts of late adolescents (124 males and 218 females), enrolled in introductory psychology courses, was assessed. Subjects rated 24 body characteristics in terms of 1) how physically attractive they assumed these parts of their bodies were, and 2) how physically effective they assumed them to be; subjects also responded to a short self-concept scale. In accordance with the theory of Erikson (1968) and of McCandless (1970), it was expected that attractiveness attitudes should contribute more to the self-concepts of females than should effectiveness attitudes, while a reverse pattern of interrelatedness was expected for males. Results indicated a higher correspondence between what are seen as attractive body parts and what are viewed as effective body components for males than for females. Moreover, findings from step-wise multiple regression analyses of each sex group's ratings of the body parts for attractiveness and effectiveness, respectively, each with the criterion variable constituting mean self-concept score, were consistent with expectations. For females, the multiple correlation between attractiveness ratings and self-concept was greater than the multiple correlation between effectiveness ratings and self-concept, and more attractiveness variables than effectiveness variables were significant predictors of self-concept. The converse of these findings were obtained with the males' data. The relevance of these results for theories of personality development were discussed.

Adolescent↗
PubMed2003

Response of oxidative stress biomarkers to a 16-week aerobic physical activity program, and to acute physical activity, in healthy young men and women.

Physical activity (PA) is associated with a reduced risk of coronary heart disease, and may favorably modify the antioxidant-prooxidant balance. This study assessed the effects of aerobic PA training on antioxidant enzyme activity, oxidized LDL concentration, and LDL resistance to oxidation, as well as the effect of acute PA on antioxidant enzyme activity before and after the training period. Seventeen sedentary healthy young men and women were recruited for 16 weeks of training. The activity of superoxide dismutase in erythrocytes (E-SOD), glutathione peroxidase in whole blood (GSH-Px), and glutathione reductase in plasma (P-GR), and the oxidized LDL concentration and LDL composition, diameter, and resistance to oxidation were determined before and after training. Shortly before and after this training period they also performed a bout of aerobic PA for 30 min. The antioxidant enzyme activity was also determined at 0 min, 30 min, 60 min, 120 min, and 24 h after both bouts of PA. Training induces an increase in GSH-Px (27.7%), P-GR (17.6%), and LDL resistance to oxidation, and a decrease in oxidized LDL (-15.9%). After the bout of PA, an increase in E-SOD and GSH-Px was observed at 0 min, with a posterior decrease in enzyme activity until 30-60 min, and a tendency to recover the basal values at 120 min and 24 h. Training did not modify this global response pattern. Regular PA increases endogenous antioxidant activity and LDL resistance to oxidation, and decreases oxidized LDL concentration; 30 min of aerobic PA decreases P-GR and B-GSH-Px activity in the first 30-60 min with a posterior recovery.

Adult↗
PubMed1995

The AAPM/RSNA physics tutorial for residents. Physics of PET.

Positron emission tomography (PET) is a coalition of physics, chemistry, physiology, and medicine united in an effort to measure physiologic parameters noninvasively. A PET study consists of producing radiotracers, synthesizing radiopharmaceuticals from the tracers, administering the radiopharmaceutical to a patient, measuring the resulting radioactivity distribution in an organ of interest, and interpreting the activity distribution as a function of physiologic parameters. Radiotracers are produced with medical accelerators that are characterized by the amount of time required to produce a set amount of radiotracer. Radiopharmaceutical production requires automated or remote synthesis modules that are characterized by their efficiency for incorporating the radiotracer into a radiopharmaceutical and the length of time and amount of human interaction required. Imaging protocols must consider sources of image artifacts, the method by which the images will be analyzed, and the uncertainty in the final result. Each of these areas has implications for the cost of the procedure, patient comfort, and the information obtainable from the study. This article gives an overview of these areas and defines the principles that can be used to distinguish between and the consequences of different approaches.

Humans↗
PubMed1996

The AAPM/RSNA physics tutorial for residents. Physics of SPECT.

Single-photon emission computed tomography (SPECT) provides three-dimensional (3D) image information about the distribution of a radiopharmaceutical injected into the patient for diagnostic purposes. By combining conventional scintigraphic and computed tomographic methods, SPECT images present 3D functional information about the patient in more detail and higher contrast than found in planar scintigrams. A typical SPECT system consists of one or more scintillation cameras that acquire multiple two-dimensional planar projection images around the patient. The projection data are reconstructed into 3D images. The collimator of the scintillation camera has substantial effects on the spatial resolution and detection efficiency of the SPECT system. Physical factors such as photon attenuation and scatter affect the quantitative accuracy and quality of SPECT images, and various methods have been developed to compensate for these image-degrading effects. In myocardial SPECT, an important application of SPECT, recent use of attenuation compensation methods has provided images with reduced artifacts and distortions caused by the non-uniform attenuation in the chest region and by the diaphragmatic and breast attenuation. Attenuation-compensated myocardial SPECT images have the potential to improve clinical diagnosis by reducing the false-positive and false-negative detection of myocardial defects. In the future, further improvement in SPECT images will be realized from the continuous development of new radio-pharmaceuticals for new clinical applications, instrumentation with high spatial resolution and detection efficiency, and image reconstruction algorithms and compensation methods that reduce the image-degrading effects of the collimator-detector, attenuation, and scatter.

Humans↗
PubMed1982

Obesity, diabetes mellitus and physical activity--metabolic responses to physical training in adipose and muscle tissues.

The demand of the untrained skeletal muscle to produce additional mechanical work by utilizing more nutrients is the origin of the structural and metabolic adaptation of the muscle. The expanding capillary surface, in response to a lower vascular resistance during repeated contraction, enables the different fibre types to increase their oxygen extraction, and to adapt their uptake of substrates (glucose, FFA). The muscle fibre types in humans are selectively recruited for differing work intensity but the oxidative potential (SDH) increases in all types with long-term physical training. Details of the mechanism by which insulin promotes glucose uptake are unclear but there is some evidence that the hormonal stimulation involves cellular uptake of the insulin-receptor complex of the membrane. Hypoxia and raised cytoplasmic levels of calcium in muscle cells after work exert an insulin-like action on glucose uptake, which may be ascribed to the intracellular acidity.--The interrelationship between glucose and FFA oxidation is in part regulated by known key enzymes of the contracting muscle, but the exact extramuscular substrate mobilization appears to require both hormonal and supplementary feed-back control in storage organs.--During prolonged muscular exercise, the successive utilization of carbohydrate and fat from endogenous and exogenous stores can, however, in principle be attributed to known hormonal regulation.--Oral intake of glucose solution before and during work evokes a prolonged glucose utilization with relative hyperinsulinemia and hypoglucagonemia, preventing hepatic glycogenolysis. A prerequisite for successful endurance training is the improved capacity to use FFA as substrate. The necessary lipolysis in adipocytes is mainly mediated by an increased cellular exposure and sensitivity to catecholamines, but the delayed adaptation of the fat cells to their hormonal environment, especially insulin, in relation to the progress of the training is likely to modify the lipolytic response.

Adipose Tissue↗
PubMed1981

[Correlations between the components of the test for the evaluation of physical performance II of the Canadian Association of Health, Physical Education and Recreation].

The Fitness-Performance Tests developed in 1965 by the Canadian Association for Health, Physical Education and Recreation have been criticized with regard to the validity of the 300 yard run as an endurance measure and with regard to the redundance of some items involving lower limb performance. The purposes of this study were to identify a more appropriate endurance performance test item and to analyze the inter-dependence of the items which utilize leg power in their performance. A sample of 9000 young Canadians aged 6 to 17 years, was randomly selected from the 10 provinces and the 2 territories. Correlation coefficients were calculated between: standing long jump, the 50 m. run, and the endurance run (800 m. for 6-9 years, 1600 m. for 10-12 years and 2400 m. for 13-17 years). Among the different age and sex groups, the correlations between the endurance run and the 50 m. run varied from 0.40 to 0.49. The correlations between standing long jump, the agility run (4 x 10 m.) and the 50 m. run were from 0.69 to 0.83 for all the boys and girls. The correlations between these three items are even lower when performances are analyzed by age and sex groups. The highest variations are mainly in the preadolescent period for both sexes.

Adolescent↗
PubMed1980

[Effect of physical exertion on intraocular pressure in healthy persons with similar degrees of physical fitness].

35 young, healthy men were divided at random into two groups. Each of them made physical effort of different intensity and different quantity of the work performed. It was found that intraocular pressure was decreased in both groups but its drop was bigger in the group whose work was more strenouos. From the difference of performance of intraocular pressure in both the controlled groups we can conclude the degree of reduction of intraocular pressure and length of its duration may depend on quantity of the work performed. The pulse and blood pressure seem not to affect the intraocular pressure.

Adult↗